首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   119篇
  免费   0篇
  国内免费   1篇
系统科学   1篇
丛书文集   1篇
理论与方法论   1篇
现状及发展   49篇
研究方法   10篇
综合类   58篇
  2017年   1篇
  2013年   1篇
  2012年   3篇
  2011年   2篇
  2010年   1篇
  2009年   1篇
  2008年   4篇
  2007年   8篇
  2006年   2篇
  2005年   7篇
  2004年   3篇
  2003年   1篇
  2002年   7篇
  2001年   2篇
  2000年   4篇
  1999年   2篇
  1995年   2篇
  1994年   1篇
  1992年   2篇
  1991年   2篇
  1990年   3篇
  1985年   2篇
  1983年   3篇
  1982年   1篇
  1980年   3篇
  1979年   9篇
  1978年   4篇
  1977年   3篇
  1976年   2篇
  1974年   2篇
  1973年   4篇
  1971年   3篇
  1970年   8篇
  1969年   3篇
  1968年   3篇
  1967年   2篇
  1966年   6篇
  1965年   3篇
排序方式: 共有120条查询结果,搜索用时 62 毫秒
11.
A radiation hybrid map of the rat genome containing 5,255 markers.   总被引:17,自引:0,他引:17  
A whole-genome radiation hybrid (RH) panel was used to construct a high-resolution map of the rat genome based on microsatellite and gene markers. These include 3,019 new microsatellite markers described here for the first time and 1,714 microsatellite markers with known genetic locations, allowing comparison and integration of maps from different sources. A robust RH framework map containing 1,030 positions ordered with odds of at least 1,000:1 has been defined as a tool for mapping these markers, and for future RH mapping in the rat. More than 500 genes which have been mapped in mouse and/or human were localized with respect to the rat RH framework, allowing the construction of detailed rat-mouse and rat-human comparative maps and illustrating the power of the RH approach for comparative mapping.  相似文献   
12.
R Kameji  H Otsuka  Y Hayashi 《Experientia》1980,36(4):441-442
Collagen synthesis in the pulmonary artery in animals with pulmonary hypertension was studied using monocrotaline-treated rats as a model. Incorporation of 14C-lateled proline into collagenase-digestible protein in the pulmonary artery was found to be 4-5 times higher in monocrotaline-treated rats than in control rats.  相似文献   
13.
Summary A new diterpenoid named jungermanool was isolated fromJungermannia torticalyx and the structure was found to be labda-8 (17), 14-dien-9, 13-diol by chemical and spectroscopical methods.Chemical constituents fromHepaticae, Part XXIV: Part XXIII,A. Matsuo, H. Nozaki, M. Nakayama, Y. Kushi, S. Hayashi andN. Kamijo, Tetrahedron Lett.1975, 241.The authors wish to express their gratitude to Dr.T. Seki, Department of Botany, Hiroshima University, for the collection and identification of the liverwort.  相似文献   
14.
Cellular and Molecular Life Sciences - Glandular stomachs of fetal and newborn Wistar rats were transplanted s.c. after treatment in vitro with N-methyl-N′-nitro-N-nitrosoguanidine (MNNG) at...  相似文献   
15.
In natural squid liver, about 30% of the total Cd present was found in the cytosolic fraction. A large portion of this Cd was bound to high molecular weight species (mol. wt greater than 70,000). In contrast to Cd, about 60% of the total Ag occurred in the cytosolic fraction; Ag was bound mainly to low molecular weight species (mol. wt less than 20,000).  相似文献   
16.
17.
Synthesis of infectious phiX-174 bacteriophage in vitro   总被引:6,自引:0,他引:6  
R Mukai  M Hayashi 《Nature》1977,270(5635):364-366
  相似文献   
18.
Summary Collagen synthesis in the pulmonary artery in animals with pulmonary hypertension was studied using monocrotaline-treated rats as a model. Incorporation of14C-labeled proline into collagenase-digestible protein in the pulmonary artery was found to be 4–5 times higher in monocrotaline-treated rats than in control rats.  相似文献   
19.
The bony skeleton is maintained by local factors that regulate bone-forming osteoblasts and bone-resorbing osteoclasts, in addition to hormonal activity. Osteoprotegerin protects bone by inhibiting osteoclastic bone resorption, but no factor has yet been identified as a local determinant of bone mass that regulates both osteoclasts and osteoblasts. Here we show that semaphorin 3A (Sema3A) exerts an osteoprotective effect by both suppressing osteoclastic bone resorption and increasing osteoblastic bone formation. The binding of Sema3A to neuropilin-1 (Nrp1) inhibited receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation by inhibiting the immunoreceptor tyrosine-based activation motif (ITAM) and RhoA signalling pathways. In addition, Sema3A and Nrp1 binding stimulated osteoblast and inhibited adipocyte differentiation through the canonical Wnt/β-catenin signalling pathway. The osteopenic phenotype in Sema3a?/? mice was recapitulated by mice in which the Sema3A-binding site of Nrp1 had been genetically disrupted. Intravenous Sema3A administration in mice increased bone volume and expedited bone regeneration. Thus, Sema3A is a promising new therapeutic agent in bone and joint diseases.  相似文献   
20.
An unsuspected attachment mechanism may help these huge spiders to avoid catastrophic falls. Spiders spin silk from specialized structures known as abdominal spinnerets--a defining feature of the creatures--and this is deployed to capture prey, protect themselves, reproduce and disperse. Here we show that zebra tarantulas (Aphonopelma seemanni) from Costa Rica also secrete silk from their feet to provide adhesion during locomotion, enabling these spiders to cling to smooth vertical surfaces. Our discovery that silk is produced by the feet provides a new perspective on the origin and diversification of spider silk.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号